[ooc: Banzai dives into the local internet to attempt to find public records for the "building" in question (entrances, sewers, basements, electrical, phone lines, the works)
These are simply not available because it is not a public building. Given the size of the complex from orbital photos, you have a pretty good guess that it's intended as a secondary command bunker and hardline comms relay. SLDF equivalents have a guardroom and a "waiting area" where people can be processed into the back, an office or two, and a hardened area in the center or in the back where the comms equipment is (also tends to double as a small armory).
Assuming that your read of the orbitals is correct, the usual RWR internal defenses are focused around a fire team or a squad (4-8 personnel) of infantry. In your experience, RWR bunkers depend on manpower, not automation, for internal defenses, so the odds of running into command-detonated explosives or turret defenses are low. They do tend to be built heavier than SLDF equivalents, and some can initiate a computer-controlled lockdown procedure that will seal the defenders behind extremely stout doors (these last types were mainly found on Apollo - the RWR capital).
Then, probably more tricky, hack into the Rimworlds Military net to find where Gen Babcock is stationed. He might need Hawker's help with cryptography on this one.]
Normally, I'd say you have no access to that sort of info...but given that you salvaged the Guillotine and you and Hawker would have had three weeks to poke at it with your skill levels...OK.
General Babcock was rotated to a new command position in August of 2777. He commands the 118th Brigade, and of the two Mech regiments in that Brigade, the 422nd Amaris Cavaliers are his direct command.
Marshall seems to calculate odds for a few minutes. "Padre, lots of flashbangs are in order for this. If we have to clear room to room a building by ourselves we need all the edge we can get. Tear gas and respirators might even be a good call."
As a free Career/Soldier thing for both you and Kenji, as ex-infantrymen: infantry gear is sealed against gas and is hardened against both laser flashes (polarizing faceplates) and the concussion of BattleMech-grade autocannon going off nearby***. Given those facts, flashbangs, while hilarious, are not *necessarily* going to be effective against all possible adversaries. I'm not saying they may not help, but they aren't likely to be the "auto-win" button they are in MOUT today...
***Star League Sourcebook; Decision at Thunder Rift; Mercenary's Star are all sources for these points.